1. (Technical Field)
The present invention relates to a semiconductor module including power semiconductors, and a semiconductor device configured to cool the semiconductor module by using an evaporative cooler.
2. (Related Art)
A power converter installed in a hybrid car, an electric car or the like uses a semiconductor module including power semiconductor devices. To make a motor and the like driven by high-powered power converters, it is required that larger current flows through the semiconductor module, which raises a problem of an increase occurring of the amount of heat generation.
To solve the above problem, JP-A-2005-191082 discloses a semiconductor module, which is an example of a semiconductor module having high heat removal. In this semiconductor module, power semiconductor devices are arranged between a pair of heat sinks. The heat generated from the power semiconductor devices is removed from both surfaces thereof, thereby improving heat removal.
However, when using the above semiconductor module for the power converter, it is difficult to miniaturize the power converter. That is, when configuring a power converter circuit such as an inverter circuit with the above semiconductor module, more than one semiconductor module is required, which increases the number of components of the power converter circuit.
Meanwhile, it can be considered that a unified semiconductor module is configured by arranging a plurality of power semiconductor elements inside the semiconductor module. If a plurality of power semiconductor elements are arranged in the direction parallel to the main surface of a heat sink, the area of the heat sink increases. Hence, the semiconductor module cannot be prevented from increasing in size.
To solve the above problem, it can be considered that a plurality of power semiconductor elements are arranged in the direction perpendicular to the main surface of the heat sink. However, in this case, the area in which the heat sink contacts the power semiconductor element decrease, which increases heat resistance between the heat sink and the power semiconductor element. Hence, heat removal of the semiconductor module can degrade.